error[E0502]: cannot borrow `my_struct.field` as mutable because it is also borrowed as immutable
  --> $DIR/region-ends-after-if-condition.rs:26:9
   |
LL |     let value = &my_struct.field;
   |                 ---------------- immutable borrow occurs here
LL |     if value.is_empty() {
LL |         my_struct.field.push_str("Hello, world!");
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ mutable borrow occurs here
...
LL |     drop(value);
   |          ----- immutable borrow later used here

error: aborting due to previous error

For more information about this error, try `rustc --explain E0502`.